package collection;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;

public class CollectionDemo2 {
    public static void main(String[] args) {

        //Collection c = new ArrayList();
        Collection c= new HashSet();
        c.add(new Point(1,2));
        c.add(new Point(3,4));
        c.add(new Point(5,6));
        c.add(new Point(7,8));
        c.add(new Point(9,0));
        boolean  b = c.add(new Point (1,2));
        System.out.println(b);//对于HashSet集合，如果添加的元素已经存在，则返回false  因为是否重复取决于元素的equals()结果
                              //对于ArrayList集合，则返回true 因为ArrayList是可重复集
        //元素1.toString(),元素2.toString()，元素3.toString()，元素4.toString()，元素5.toString()
        System.out.println(c);
        Point p = new Point(1,2);
        boolean contains = c.contains(p);
        System.out.println("是否包含:"+contains);//true
        boolean remove =  c.remove(p) ;
        System.out.println("是否删除:"+remove);// true   一般都不接收boolean结果
        System.out.println(c);
    }
}
